1. Field of the Invention
The present invention relates to a motor vehicle headlamp, and, more particularly, to a motor vehicle headlamp comprising an aiming adjustment device which is provided with an adjustment prevention mechanism to prevent any change of the aiming adjustment of the headlamp after shipment from the manufacturer that was completed during a manufacturing process.
2. Background Art
FIG. 5 shows a conventional headlamp 90 and an automotive body 30. Since a manufacturing error is inevitable on the headlamp 90 after the headlamp 90 is manufactured, some adjustments are required after the headlamp 90 is mounted on the automotive body 30 so that a specified beam direction can be obtained.
Accordingly, the headlamp 90 is equipped with an aiming adjustment device 91 that, for example, enables a reflector to be adjusted vertically and horizontally. An adjusting element 91a of said aiming adjustment device 91, for example, extends from an external surface of a housing 90a of the headlamp 90 to allow for adjustment of headlamp 90 after headlamp 90 is mounted on the automotive vehicle. Thus, the headlamp 90 can be easily adjusted from the outside of housing 90a after the headlamp 90 is mounted on the automotive vehicle.
However, if the adjusting element 91a is extended to the external surface of the housing 90a and is exposed as mentioned above, even a user of the automotive vehicle is capable of adjusting headlamp 90. This allows for the possibility of improper adjustment by users who do not have full and accurate knowledge about aiming. Depending on destination countries, some standards require an adjustment prevention mechanism 92 disposed so as to prevent users from manipulating the adjusting element 91a.
The conventional adjustment prevention mechanism 92 consists of a cover 92a for covering said adjusting element 91a and a mounting screw 92b (or a rivet depending on the case used) for fixing the cover 92a on the housing 90a. After completion of the aiming adjustment, the manufacturer mounts the cover 92a with the mounting screw 92b to prevent any adjustment thereafter.
When the headlamp 90 is mounted on an actual automotive body 30, however, in most cases almost no gap is left between the housing 90a and the automotive body 30, as is shown in FIG. 5. After completion of the aiming adjustment, there hardly remains a workspace for mounting said cover 92a of the adjustment prevention mechanism 92 and fixing the mounting screw 92b. Even if said cover 92a can be mounted, the prior art for mounting adjustment prevention mechanisms has often created one or more collateral problems including:
(a) unavailability of a workspace for manipulating a tool such as a screw driver for fixing said mounting screw 92b; PA1 (b) a need for special apparatus and tools; PA1 (c) a need for welding the cover 92a; PA1 (d) a decrease in the productivity; and/or PA1 (e) an increase in production costs. PA1 an external rib which, having a tool insertion hole, forms part of a headlamp assembly and surrounds said adjusting element, and PA1 a cover member of which external wall fits to an internal wall of said external rib.